Safety-fuse.



No. 874,798. PATENTED DBG. 24, 1907.

1. SACHS.

SAFETY FUSE.

PPLIOATION FILED Arx. 1a, 190s. nmmwnn SEPT. 11I 1901.

N UNITED STATES-PATENT OEE-ICE.

JOSEPH SACHS, OE HARTFORD, CONNECTICUT, ASSIGNOR To THE SACHS COMPANY, OF HARTFORD, CONNECTICUT, A CORPORATION OE CONNECTTCUT.

` SAFETY-FUSE.

specification ef Leteereratent.

patented nec. 24, 19o?.

lApplioatlon lled April 18. 1906. Serial No. 812.302. Renewed September 11 1907. Serial No. 392,869.

To all whom 'it may concern: Be it known that I, JOSEPH SACHS, a cit1- zen of the United States, residing atv Hartford, in the county of Hartford and State of Connecticut, have invented an Improvement in Safety-Fuses, of which the following is a specification. A

My invention relates to safety fuses of the type used with telegraph and telephone systems and adapted for very small current service. In the past such fuses have been constructed of heating coils'or springs con-y sisting of resistance wires; one end of each of the s rings or Coils being joined together by fusibie solder `so that when the current is passed throu h the convolutions of the coiled springs whic wer kept under tension, lthe heat produced would cause the melting of the fusible j oint and hence a rupture or opening at this point. ,The objection to this construction in the past has been due to the fineness of. the wires necessary in the construction of the coiled springs and the difficulty of assembling and maintaining them in a rlgid position, and'hence, as heretofore constructed, such fuses ,have been readily injured by handling ,both in construction and service,-

aixing the/'joint to be ruptured mechanica Tldre object of my present invention is to provide a construction for this type of fuse which willl insure rigidity and ermanenc in the heat coil structure and Ipaccomplisli this result by providing the heating coils and the wires extendin from their ends to the circuitterminalswit asuitable holderhavin located therein a pocket in which the coile portion and joint are protected.

. In carrying out my present invention, I preferably employ a casing, terminals thereon, a holder of insulating material fitting within said casing, and provided centrallywith a pocket, resistance wires,` each connected at one end with one of said terminals, extending into'the said holder and havin a coiled portion within the said pocket, and a fusible connection ,between the coiled ends of said wires within the said pocket.

gether, or ma e in two or more pieces suitably astened together, or otherwise as may be desired, but in any instance the holder cis provided with a` ocket 2, formed preferably centrally by epressions in therespective members thereo and the pocket 2 may be entirely inclosed or open at one Side and along one edge of the strip c as shown in Fig. 7.

e, designates wires preferably of- German silver or other high resistance material, each electrically Connected at one end to a terminal b passi between the parts ofthe strip c and into t e pocket 2 therein, where these wires are coiled as shown at 3, 4, respectively, and ltheir inner ends are electrically connected by a'dro of solder 5 Or other fusi- 'ble material, and desired, the ends of the tube a between the terminals and the ends of the strip c may be filled with an asbestos fiber or other insulating material as indicated at 6.

It will be apparent that the coiled ends of the wires within the pocket of the said holder not only concentrate the heat produced in the wire but also being under tension, effect a se aration of the extremities thereof when the joint is ruptured, and that the delicate fuse structure is protected by being supported rigidly within the holder.

While I prefer to employ a tubular casing provided with suitable terminals it will be understood that I may dispense with the tube, Without departingrom the nature and spirit of my invention, and as shown in Figs; t

5 and 6, I may employ terminals b b, between which are Clam ed the respective ends ofl the holder c of insuiatin material inwhich the pocket 2 is formed. esistance wires d e are each connected at one end to a terminal b andextend through the strip c into the pocket 2 Where `the other ends of the wires glued or otherwise secured to` lloo are coiled as at 3 4, res ectively and the extremities are electricalljr connected by the fusible joint 5.

l claim'as my invention:

'L A safety fuse comprising terminals, a holder of insulating material, a pocket integral With said holder and wires connected at the parts thereof secured together, a pocket i formed by the parts of said holder, and high resistance Wires electrically connected at one end with the respective terminals and passing -between the parts of said holder and at the other ends coiled and electrically connected by a fusible joint Within said pocket.

4. A safety fuse comprising a tube, terminals therefor, a holder of insulating mate# rial, a pocket in said holder and wires connected at one end with the res ective termi; nals and passed into said hol er and at the other electrically connected with each other by a fusible joint Within the said pocket.

' 5. A safet fuse comprising a tube, terminals there or, a holder of insulating material, Va pocket in said holder, and high resist ance wires electricallyconnected at one end to the respective terminals and assed into lsaid holder and at the other coile With their extremities electrically connected by a 'fusible joint Within said pocket. v

6. A safety fuse comprising a tube, terminals thereon, a two-part holder of insulating material with the parts thereof secured together, a pocket formed by the parts of said holder, and high resistance Wires electricallyconnected at one end With therespective terminals and assin between the parts of said holder an at t e other ends coiled and electrically connected by a fusible joint Within said pocket.

`7. A safety fuse com rising a holder of insulating material, a poc et therein, heating coils under tension in said pocket, and a fusible joint connectin ,one end of each coil Within the pocket, t e other ends extending throu lfthe holder. v

8. i safety fuse comprising a tube, terminals thereon, a holder of insulating material Within said. tube, a pocket in said holder, heating coilswithin said pocket, and a fusible joint connectin one end of each coil Within the pocket, t e other ends extending through the said holder and being electrically connected to the said teminals.

. 9. A safety fuse com rising a tube, end caps thereon, a holder o insulating material withinsaid tube, a'pocket in said holder, heating coils within said pocket, and a fusible joint connecting one end of each coll Within the pocket, the other ends extending through the said holder and being electrically connected to the said end caps.

10. A safety fuse comprising a flat strip of insulating material with its parts so folded and connected together as'to providea pocket therein centrally of its len th, heating coils in said tween vt e ends of the coils in the pocket, the other ends of the coils extending to the opposite extremities of said strip.

plocketyand a fusib e connectionl be-` 1 1. A safety fuse comprising a tube, terminals therefor, a flat strip of insulating ma# terialfwithin said tube and having its parts so folded and held together as to provide a pocket therein, centrally of its length, heat ing coils in said pocket, and a fusible connection between the ends of the coils in the pocket, the other ends of the coils extending to the opposite extremities of the said strip and being electrically'connected to said terminals.

12. A safety fuse comprising a tube, end caps therefor, a flat strip of insulating `material Within said tube and having its parts so folded and held to ether as to rovide a pocket therein centrally of its lengt heating coils in said pocket, and ay fusible connection between the ends of theccoils in the pocket, the other ends of the coils extending to the opposite extremities lof the said stri and being electrically connected to said en ca s.

igned by me this 9th da of A ril, 1906.

- JOS PH ACHS. Witnesses:

GEO. T. PINCKNEY, B. M. ALLEN. 

